title: A method for improving the light intensity distribution in dental light-curing units.
abstract: A method for improving the uniformity of the radiation light from dental light-curing units (LCUs), and the effect on the polymerization of light-activated composite resin are investigated. Quartz-tungsten halogen, plasma-arc, and light-emitting diode LCUs were used, and additional optical elements such as a mixing tube and diffusing screen were employed to reduce the inhomogeneity of the radiation light. The distribution of the light intensity from the light guide tip was measured across the guide tip, as well as the distribution of the surface hardness of the light-activated resin emitted with the LCUs. Although the additional optical elements caused 13.2-25.9% attenuation of the light intensity, the uniformity of the light intensity of the LCUs was significantly improved in the modified LCUs, and the uniformity of the surface hardness of the resin was also improved. Our results indicate that the addition of optical elements to the LCU may be a simple and effective method for reducing inhomogeneity in radiation light from the LCUs.
authors.affiliation: Department of Biomaterials Science, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8544, Japan. hiro@dent.kagoshima-u.ac.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Arikawa
authors.forename: Hideo
authors.initials: H
authors.lastname: Takahashi
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Minesaki
authors.forename: Kouichi
authors.initials: K
authors.lastname: Muraguchi
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsuyama
authors.forename: Takahito
authors.initials: T
authors.lastname: Kanie
authors.forename: Seiji
authors.initials: S
authors.lastname: Ban
mesh_terms: D003188:Composite Resins / Q000737:chemistry / Q000528:radiation effects; D055117:Curing Lights, Dental / Q000145:classification / Q000592:standards*; D003764:Dental Materials / Q000737:chemistry / Q000528:radiation effects; D004867:Equipment Design; D005374:Filtration / Q000295:instrumentation; D006244:Hardness; D006801:Humans; D008027:Light; D008422:Materials Testing; D055668:Photochemical Processes; D058105:Polymerization; D011874:Radiometry; D013499:Surface Properties
chemical_list: D003188:Composite Resins; D003764:Dental Materials